Adjustable eyeglass



(Modem I. R. WOODWARD.

ADJUSTABLE EYEGLASS.. No. 261,799. Patented July 25, 1882.

WITNESSES INVENTOR: a; @wmw $3 BY, MW

' ATTORNEYS.

N. PETERS Phulo-lillmgmphnr. Wnuhi n nnnnnnn c.

, UNITED STATES PATENT OFFICE.

FRANK R. WOODWARD, OF HILL, NEW HAMPSHIRE.

ADJUSTABLE EYEGLASS.

SPECIFICATION forming part of Letters Patent No. 261,799, dated July 25, 1882. Application filed September 27, 1881. Renewed June 28, 1882. (ModeL) To all whom it may concern Be it known that -I, FRANK R. WOODWARD, of Hill, in the county of Merrimack and State of New Hampshire, have invented a new and Improved Adjustable Eyeglass Spring, of which the following is a full, clear, and exact specification.

The object of my invention is to facilitate the adjustment of the tension of an eyeglassspring.

The invention consists in an eyeglass-sprin g formed of two spring-strips attached to the respective lens-frames, one of'the springs being provided with a longitudinal socket for receiving the end of the other spring,which can slide therein, thereby permitting the spring to be shortened or lengthened, whereby its tension is diminished or augmented.

Reference is to be had to the accompanying drawings, forming part of this specification, in which similar letters of reference indicate corresponding parts in all the figures.

Figure l is a longitudinal elevation of an eyeglass provided with my improved adjustable spring, the glasses being shown folded, parts shown in section. Fig. 2 is a longitudinal elevation of the same opened, parts shown in section. Fig. 3.is a plan view of the same, showing it opened. Fig. 4 is a detail longitudinal sectional elevation of the spring.

'The eyeglass-frames A A are united by a combination-springformed of two spring-strips, B B, attached to the lugs O O of the frames A A, respectively. A longitudinal socket, D, formed of a plate the longitudinal sides of which are doubled over on the top, is attached to the upper surface of the spring B at the end of the same. The socket D is of such width that it can receive the spring-strips B, which can slide longitudinally in this socket D. The

end B of the spring-strip B is bent upward after having been passed through the socket D, so that this spring'strip cannot be withdrawn from the socket D accidentally. The spring-strip B must fit so closely in the socket D that there will be sufficient friction to hold the spring-strip B in any desired position in the socket D; Aslide, E, is held on the springstrip B in such a manner that it can slide on the same. The frame A is provided with a handle-loop, F, and a pin, H, and the frame A is provided witha hook, G, like an ordinary eyeglass.

The socket D may be made of a separate piece attached to the spring-stripB; or it can be made integral with this strip, the end of this strip B being widened, and then folded over on the top of the strip.

The operation is as follows: If the eyeglass is to be folded, the frames are separated as much as possible-that is to say, the springis lengthened-the bend B of the spring B preventing this spring from being withdrawn from the socket D accidentally. When thus lengthened the spring is more flexible, and can be bent without breaking, as is shown in Fig. 1. The spring has very little tension when thus lengthened, and cannot hold the eyeglass on the nose. If the tension of the spring is to be augmented, the spring must be shortened, which is accomplished by moving the frames A A toward each other in such a manner that the spring-strip B will slide through the socket D. By passing the spring-strip B through the socket D a greater or less distance the tension of the spring is increased more or less. The slide E serves as a guide for the adjustment of the spring, for the guide is adjusted at a certain position on the spring-strip B corresponding to a certain tension. If this tension of the spring is desired, the spring-strip B need only be passed through the socket D until the socket rests against the slide or guide E. Any other guide may be used in place of the slide or-guide E. V

The hereindescribed spring is much more durable than the ordinary eyeglass-spring, for its tension can be so decreased that it cannot possibly be broken while being folded.

Having thus described my invention, I claim,

as new and desire to secure by Letters Patent In an eyeglass, the combination, with the spring B, secured to the lens-frame A and provided with the socket D at its free end, of the spring B, secured to the lens-frame A, having its free end bent upward and provided with the slide E, substantially as shown and de scribed, whereby the parts are prevented from being accidentally separated and provision made for accurately adjusting the parts to the required tension, as set forth.

F. R. WOOD WARD.

Witnesses FRANK N. PARSONS, FRANCES E. WHITE.

IOO 

